BTRFS error (device loop0): allocation failed flags 4, wanted 4096 tree-log 0, relocation: 0
BTRFS info (device loop0): space_info DATA+METADATA (sub-group id 0) has 716800 free, is full
BTRFS info (device loop0): space_info total=11534336, used=450560, pinned=2625536, reserved=270336, may_use=7471104, readonly=0 zone_unusable=0
BTRFS info (device loop0): global_block_rsv: size 983040 reserved 983040
BTRFS info (device loop0): trans_block_rsv: size 0 reserved 0
BTRFS info (device loop0): chunk_block_rsv: size 0 reserved 0
BTRFS info (device loop0): delayed_block_rsv: size 65536 reserved 65536
BTRFS info (device loop0): delayed_refs_rsv: size 6422528 reserved 6418432
BTRFS info (device loop0): block group 5242880 has 1638400 bytes, 368640 used 1269760 pinned 0 reserved 0 delalloc 0 super 0 zone_unusable (0 bytes available) 
BTRFS info (device loop0): block group has cluster?: no
BTRFS info (device loop0): 0 free space entries at or bigger than 4096 bytes
BTRFS info (device loop0): block group 6881280 has 1638400 bytes, 81920 used 1331200 pinned 225280 reserved 0 delalloc 0 super 0 zone_unusable (0 bytes available) 
BTRFS info (device loop0): block group has cluster?: no
BTRFS info (device loop0): 0 free space entries at or bigger than 4096 bytes
BTRFS info (device loop0): block group 8519680 has 8257536 bytes, 0 used 24576 pinned 45056 reserved 0 delalloc 0 super 0 zone_unusable (8187904 bytes available) 
BTRFS critical (device loop0): entry offset 8589312, bytes 8187904, bitmap no
BTRFS info (device loop0): block group has cluster?: no
BTRFS info (device loop0): 1 free space entries at or bigger than 4096 bytes
BTRFS info (device loop0): 8187904 bytes available across all block groups
------------[ cut here ]------------
BTRFS: Transaction aborted (error -28)
WARNING: fs/btrfs/extent-tree.c:3235 at __btrfs_free_extent+0x1d81/0x3f40 fs/btrfs/extent-tree.c:3235, CPU#0: kworker/u4:16/3017
Modules linked in:
CPU: 0 UID: 0 PID: 3017 Comm: kworker/u4:16 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound btrfs_async_reclaim_data_space
RIP: 0010:__btrfs_free_extent+0x1d84/0x3f40 fs/btrfs/extent-tree.c:3235
Code: ae 0b 00 00 e8 ed 80 d9 fd 84 c0 0f 84 99 02 00 00 e8 70 a7 f3 fd e9 97 0b 00 00 e8 66 a7 f3 fd 48 8d 3d ff f1 dc 0b 44 89 e6 <67> 48 0f b9 3a e9 87 e9 ff ff e8 bd 9d 8f 07 89 c3 31 ff 89 c6 e8
RSP: 0018:ffffc90002d5ef20 EFLAGS: 00010293
RAX: ffffffff83ce1a8a RBX: 0000000000000000 RCX: ffff8880408a8000
RDX: 0000000000000000 RSI: 00000000ffffffe4 RDI: ffffffff8fab0c90
RBP: ffffc90002d5f0d0 R08: ffff8880408a8000 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000000 R12: 00000000ffffffe4
R13: dffffc0000000000 R14: 00000000ffffffe4 R15: ffff888041b94001
FS:  0000000000000000(0000) GS:ffff88808d22a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efda730fad8 CR3: 0000000011e6d000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 run_one_delayed_ref fs/btrfs/extent-tree.c:-1 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1973 [inline]
 __btrfs_run_delayed_refs+0xe6a/0x3af0 fs/btrfs/extent-tree.c:2048
 btrfs_run_delayed_refs+0xe6/0x3a0 fs/btrfs/extent-tree.c:2160
 btrfs_commit_transaction+0x28b/0x3b10 fs/btrfs/transaction.c:2229
 flush_space+0x4dd/0xd20 fs/btrfs/space-info.c:921
 do_async_reclaim_data_space+0x29a/0x520 fs/btrfs/space-info.c:1437
 btrfs_async_reclaim_data_space+0x41/0x90 fs/btrfs/space-info.c:1485
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
----------------
Code disassembly (best guess):
   0:	ae                   	scas   %es:(%rdi),%al
   1:	0b 00                	or     (%rax),%eax
   3:	00 e8                	add    %ch,%al
   5:	ed                   	in     (%dx),%eax
   6:	80 d9 fd             	sbb    $0xfd,%cl
   9:	84 c0                	test   %al,%al
   b:	0f 84 99 02 00 00    	je     0x2aa
  11:	e8 70 a7 f3 fd       	call   0xfdf3a786
  16:	e9 97 0b 00 00       	jmp    0xbb2
  1b:	e8 66 a7 f3 fd       	call   0xfdf3a786
  20:	48 8d 3d ff f1 dc 0b 	lea    0xbdcf1ff(%rip),%rdi        # 0xbdcf226
  27:	44 89 e6             	mov    %r12d,%esi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 87 e9 ff ff       	jmp    0xffffe9bb
  34:	e8 bd 9d 8f 07       	call   0x78f9df6
  39:	89 c3                	mov    %eax,%ebx
  3b:	31 ff                	xor    %edi,%edi
  3d:	89 c6                	mov    %eax,%esi
  3f:	e8                   	.byte 0xe8